A continuously variable transmission (CVT) is a transmission that continuously varies a speed ratio between an output speed and an input speed. One type of a CVT is a belt-type that varies the speed ratio by varying the distance between sheaves of a pulley so the distance of the belt to a rotational axis of the pulley varies. Another type of CVT is a spherical-type that utilizes spherical speed adjusters, such as power adjusters, balls, planets, spherical gears or rollers. The spherical speed adjustors in this embodiment have tiltable axis of rotation that are adapted to be adjusted to achieve a desired ratio of input speed to output speed.
For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for an effective and efficient method of controlling the variable shifting of a CVT.